LXR linux/arch/powerpc/include/asm/code-patching.h

   1#ifndef _ASM_POWERPC_CODE_PATCHING_H
   2#define _ASM_POWERPC_CODE_PATCHING_H
   3
   4/*
   5 * Copyright 2008, Michael Ellerman, IBM Corporation.
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public License
   9 * as published by the Free Software Foundation; either version
  10 * 2 of the License, or (at your option) any later version.
  11 */
  12
  13#include <asm/types.h>
  14#include <asm/ppc-opcode.h>
  15
  16/* Flags for create_branch:
  17 * "b"   == create_branch(addr, target, 0);
  18 * "ba"  == create_branch(addr, target, BRANCH_ABSOLUTE);
  19 * "bl"  == create_branch(addr, target, BRANCH_SET_LINK);
  20 * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK);
  21 */
  22#define BRANCH_SET_LINK 0x1
  23#define BRANCH_ABSOLUTE 0x2
  24
  25unsigned int create_branch(const unsigned int *addr,
  26                           unsigned long target, int flags);
  27unsigned int create_cond_branch(const unsigned int *addr,
  28                                unsigned long target, int flags);
  29void patch_branch(unsigned int *addr, unsigned long target, int flags);
  30void patch_instruction(unsigned int *addr, unsigned int instr);
  31
  32int instr_is_relative_branch(unsigned int instr);
  33int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr);
  34unsigned long branch_target(const unsigned int *instr);
  35unsigned int translate_branch(const unsigned int *dest,
  36                              const unsigned int *src);
  37
  38static inline unsigned long ppc_function_entry(void *func)
  39{
  40#ifdef CONFIG_PPC64
  41        /*
  42         * On PPC64 the function pointer actually points to the function's
  43         * descriptor. The first entry in the descriptor is the address
  44         * of the function text.
  45         */
  46        return ((func_descr_t *)func)->entry;
  47#else
  48        return (unsigned long)func;
  49#endif
  50}
  51
  52#endif /* _ASM_POWERPC_CODE_PATCHING_H */
  53